#include"string.h"

int main()
{
	xjc::string a;
	a.print();
	xjc::string b("abcdef");
	b.print();
	xjc::string c = b;
	c.print();
	c += b;
	c.print();
	std::cout << b[2] << '\n';
	c.insert(3, "xiaojiacheng");
	c.print();
	return 0;
}